1. Field of the Invention
This invention relates in general to discoid-shaped aircraft and in particular to an inverted cone airfoil which uses a triangularly-shaped tail section to provide flight stabilization.
2. Description of the Prior Art
Conventional aircraft rely on narrow extended wing structures which are designed, when quickly passed through the air, to create the pressure differential needed for lift. The same principle has been applied to aircraft utilizing a single annular wing structure, such as a saucer or cone shaped airfoil. These foils have typically relied on propeller rotation, external ailerons, or their own rotational inertia for stability.
Most of the known prior art relating to the present invention is concerned primarily with the shape of the airfoil. U.S. Pat. Nos. 2,826,860, issued to L. F. Ashley et al., 2,936,972, issued to J. Zinavage, and 2,947,496, issued to A. L. Leggett disclose saucer or cone shaped airfoils. In some instances, the cone has been truncated, forming a centerered circular opening. For example, U.S. Pat. No. 3,580,580 issued to J. D. Wark et al., discloses a simple aerial spinning disk which is comprised of a generally flat annular wing with a centered circular opening and downwardly extending inner and outer flanges. Similarly, U.S. Pat. Nos. 3,525,484, issued to L. E. Mueller, and 3,603,033, issued to L. E. Mueller, also disclose saucer shaped airfoils having ducted fan-type propulsion systems in the concentric circular opening.
U.S. Pat. No. 2,718,364, issued to E. L. Crabtree discloses an aircraft having an annular cone fuselage with a circular central aperture. An air control device fits into the aperture and is elevated when used as the principal air control element. Separate propulsion systems are used for horizontal and vertical flight. U.S. Pat. No. 2,730,312, issued to L. W. Crookes, discloses a discoid-shaped aircraft which includes a rear vertical stabilizer.